Abstract

Soybean plants have high protein content and can be used as a supplementary source of high-protein feed. To map quantitative trait loci (QTL) for the content of crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and dry weight of plant (DWP) in R2 stage of soybean, two recombinant inbred lines, RIL3613 and RIL6013, containing 134 and 156 RILs, derived from the cross of Dongnong L13 × Heihe 36 and Dongnong L13 × Henong 60, were planted for two consecutive years. Based on a simple sequence repeat (SSR) linkage map, QTLs of CP, NDF, ADF and DWP were mapped by interval mapping (IM) and inclusive composite interval mapping method (ICIM) using additive effect, epistatic effect and environmental interaction model. The variance components of genotype, environment and genotype × environment (G × E) interaction for quality and yield traits in the two RIL populations were significant under multiple environmental conditions. Eighteen additive effect QTLs on 10 of 20 soybean chromosomes explained 7.02%–15.67% and 2.13%–11.42% of the phenotypic variation in RIL3613 and RIL6013, respectively. Three epistatic QTL pairs related to CP and six ones for DWP were identified. Eight additive effect QTLs for CP, eight ones for NDF, three ones for ADF, and another three ones for DWP were identified by genotype × environment interaction analysis. One epistatic QTL for CP, 11 epistatic QTL pairs for ADF and 38 ones for NDF were identified. These results can provide better understanding of the genetic basis of soybean feed quality and yield.

摘要

大豆植物蛋白质含量高，可作为高蛋白饲料的补充来源。为了绘制大豆 R2 期粗蛋白 (CP)、中性洗涤纤维 (NDF)、酸性洗涤纤维 (ADF) 和植株干重 (DWP) 的数量性状位点 (QTL)，两个重组自交系，连续两年种植了东农L13×黑河36和东农L13×河农60杂交的RIL3613和RIL6013，分别含有134和156个RIL。基于简单序列重复（SSR）连锁图，利用加性效应、上位效应和环境相互作用模型，通过区间映射（IM）和包容复合区间映射方法（ICIM）对CP、NDF、ADF和DWP的QTL进行定位。基因型的方差分量，在多种环境条件下，两个 RIL 种群的质量和产量性状的环境和基因型 × 环境 (G × E) 相互作用显着。20 条大豆染色体中的 10 条上的 18 个加性效应 QTL 分别解释了 RIL3613 和 RIL6013 表型变异的 7.02%–15.67% 和 2.13%–11.42%。确定了与 CP 相关的三个上位 QTL 对和与 DWP 相关的六个上位 QTL 对。通过基因型×环境互作分析鉴定出CP的8个加性效应QTL、NDF的8个、ADF的3个、DWP的3个。鉴定出CP的1个上位QTL、ADF的11个上位QTL对和NDF的38个上位QTL对。这些结果可以更好地了解大豆饲料质量和产量的遗传基础。